<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge,chrome=1">
    <title>浏览器升级</title>
    <style>
        *{padding:0; margin:0; border:0;}
        .box{position:absolute; left: 50%; top: 45%; width: 600px; text-align:center;
             min-height: 368px; background:#fff;border:8px solid #323232; border-radius:5px; 
             }
    </style>
</head>
<body>
    <div></div>
</body>
</html>